锈蚀对Q550E高性能钢梁抗弯承载力影响的试验研究

为研究Q550E高性能钢结构锈蚀后的力学性能，制作7片锈蚀H形高性能钢梁，利用通电加速腐蚀的方法对钢梁进行锈蚀，通过抗弯性能试验，分析锈蚀对高性能钢梁的应变、挠度、承载力以及刚度退化等的影响。试验研究表明：锈蚀显著降低了高性能H形钢梁的承载力，锈蚀率每增加1%其屈服荷载与极限荷载大约减少11 kN；随着锈蚀率的增加，钢梁延性系数均呈下降趋势；钢梁的锈蚀降低了梁的实际屈服强度，使局部屈曲提前发生；试件在达到极限荷载前应变基本符合平截面假定，表明锈蚀基本上不改变高性能钢结构的应变分布；在弹性阶段的钢梁抗弯刚度将会发生退化，其退化速度与锈蚀率呈线性关系。

Experimental Study on Effect of Corrosion on Flexural Load-carrying Capacity of Q550E High-performance Steel Girder

To study the mechanical properties of a Q550E high-performance steel structure after corrosion, seven corroded H-beams were designed and subjected to electrochemically accelerated corrosion. The effects of corrosion on the strain, deflection, bearing capacity, and stiffness degradation of high-performance steel beams were analyzed following a bending resistance test. Test results reveal that corrosion significantly reduces the bearing capacity of high-performance steel H-beams. In addition, yield and ultimate loads decrease by approximately 11 kN when the corrosion rate increases by 1%. The corrosion of steel beams reduces the actual yield strength and causes local buckling to occur in advance. The strain accords with the assumption of the plane section before the ultimate load is reached, indicating that the corrosion essentially does not change the strain distribution of beams. The flexural stiffness of beams degenerates at the elastic stage, and its degradation rate is linearly related to the corrosion rate.